Lawn mower



May 24, 1949. J. D. CAVANESS 2,471,367

LAWN MOWER Filed Oct. 1, 1945 2 Sheets-Sheet l Patented May 24, 1949came mTE r c James fli qavaness, Arlington; Tex Applicationzflctobenh1945, SerialgNo. 619 1453,

21Qlaiins; (Cl. 56'-25 .;4

This invention relates to lawn-mowers.

An object oft; this; invention; is; to; provide an electricallyopera-tedlawn mower having a horizontall'y rotatable cutting blade;

Another object of this invention" is toprovide a mower of? the-:kindWliibh'rincludes. a slip coupling between the power member and thecutting.

blade so thatin the event obstructions. arachcountered th blade may slipr ela tively to. the shaft.

Aflfurthei object of" this invention. is tqiprovide amowerroflfthis kindincluding, anelectrieimot'or rri'oiintedi on: a transvers'el the motorhaving a vertical drive shaft extending downwardly into the concave sideof the shield and the drive shaft having a rotatable cutting bladeclutched thereon for rotation in a horizonal plane.

To the foregoing objects, and others which may hereinafter more fullyappear, the invention consists of the novel construction, combinationand arrangement of parts, as will be more specifically referred to andillustrated in the accompanying drawings, but it is to be understoodthat changes, variations and modifications may be resorted to which fallwithin the scope of the invention as claimed.

In the drawings:

Figure 1 is a vertical section partly in detail of a mower constructedaccording to an embodiment of this invention,

Figure 2 is a bottom plan view of the device,

Figure 3 is a sectional view taken substantially on the line 33 ofFigure 1,

Figure 4 is a fragmentary sectional view taken on the line 4--4 ofFigure 3, and

Figure 5 is a fragmentary plan View of the coupling plate between thelower clutch member and the blade structure.

Referring to the drawings, the numeral i0 designates generally adome-shaped shield or frame member which is disposed with the concaveside thereof facing downwardly. A pair of wheels H are rotatably mountedon shafts l2 which are carried by bracket members 13 secured todiametrically opposite points on the shield or frame member ID.

A motor [4 is disposed on the upper side of the shield or frame memberI0 and secured thereon by fastening members I5. The motor l4 includesthe shaft llibelowtherclut ch member. I 'l by. fas: tening means l9.WhichIi'ssecuIedJtO. the lower end-i ofithe shaft" IB;

A cutting blade.structure generally designated as 213 is, bolted orotherwise. securedtotha plate; l8: byffastening members 2],Tliaffasteniiigi members 2]; extend j throughthe outer; portion" off theplate 1.3, as. slio'w'rimore, clearly in Figure, 4.} There maybe. as nyfast'eningrmembersfi as. maybe desired.

The blade structure. 20' includesv a supporting plate 22' which isformed with an upwardlygofisete outer portion- 23. A pair. of.uttersQZ'Q, extend from 'tlie'outer marginal edge portion of'theoffset23 and are secured to the offset portion 23 by fastening members 25. Theinner portion of each cutter blade 24 is downwardly bent as indicated at26 so as to snugly engage the upper side of the offset portion 23.

An upper clutch member generally designated as 2'! is splined on theshaft Iii as indicated at 28 and confronts the upper clutching face 29of the lower clutch member IT. The upper clutch member 21 includes a hub33 engaging about the shaft 1 6, which is formed at its lower end with aclutch plate 3! having a fibrous friction member 32 secured to the lowerside thereof by fastening members 33.

The upper clutch member 21 is constantly urged downwardly to clutchingengagement with the lower clutch member I! by means of a spring 34 whichis interposed between the hub 30 and a boss 35 formed as part of themotor M. In order to provide a means whereby the blade structure 20 mayhave relative rotating movement with respect to the shaft l6, the lowerclutch member I! is formed with a lower flange 36 having openings 3'!within which the upper ends of the fastening members 2| loosely engage,In this manner the fastening members 2| provide a loose coupling betweenthe lower clutch member I! and the blade structure 20 so that the lattermay rotate or tilt as it is being rotated.

A handle 38 is secured to the frame or shield l0 and is of desiredlength so that the device may be moved over the grass during the cuttingoperation. Blade 24, as shown in Figure 3, is provided with a forwardcutting edge 39 and with an outer cutting edge 40.

In the use and operation of this device, the motor I4 is connected bysuitable conductors to a source of electric current supply. The deviceis moved over the grass and as the blad structure 20 rotates at the samespeed as the motor shaft I6 the cutters 24 will cut the grass. As the 3blade structure 20 is loosely coupled to the lower clutch member I! andthe shaft H5, in the event the lower side of the plate 22 strili es theground or an obstruction, the blade structure may tilt as it is rotatedwithout injury to the shaft Hi.

In the event the obstruction causes it to drag on the blade structure20, the cluth member 21 may slip relative to the upper clut member [1.Normally the two clutch members, I! and 27, are clutched together androtate as a unit under the compression or tension of the expansiblespring 34.

What I claim is:

1. In a power lawn mower having a source of power, a shaft rotatable bysaid source of power, and a rotatable cutting member; coupling means foryieldably and rockably mounting said cutting member on said shaft forrotation therewith at substantially right angles to the axis thereof,said coupling means comprising fastening means forming a shoulder on theend of said shaft, a first element slidably carried by said shaft, asecond element fixed to said cutting member and loosely engaging saidshaft between said first element and said fastening means, one of saidelements being formed with a flat surface and the adjacent surface ofthe other of said elements being convex, means fixed on said secondelement engaging said first element for rotation therewith, and a clutchmember rotatable with said shaft and adapted to frictionally engage saidfirst element.

2. In a power lawn mower having a rotatable shaft and a rotatablecutting member; coupling means for yieldably and rockably mounting saidcutting member on said shaft for rotation therewith, at substantiallyright angles to the axis thereof, said coupling means comprisingfastening means on the end of said shaft, a lower clutch member slidablycarried by said shaft and formed with a flat lower surface, aconcavo-convex plate fixedly mounted on said cutting member with theconvex surface thereof facing outwardly, and formed with a centralopening loosely engaging said shaft between said lower clutch member andsaid fastening means with said convex surface abutting said flat lowersurface, means on said concave-convex plate engaging said lower clutchmember for rotation therewith, and an upper clutch member rotatable withsaid shaft and adapted to frictionally engage and lower said clutchmember.

JAMESv D. CAVANESS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 762,975 l'ihthony June 21, 19041,503,446 Hedglon July 29, 1924 2,076,056 Woodford Apr. 6, 19372,302,472 Power Nov. 17, 1942 2,329,185 Coddington Sept. 14, 19432,335,574 Thompson et al. Nov. 30, 1943

